The high-energy, shaggy-haired duo sit crosslegged on the pavement in the videos, pounding at their instruments and bopping their bodies to as they sing songs that are equal parts humour and political critique.

In a typical tune, "Blabla Halal," the pair cite the recent debate over Islamic meat as an example of the beside-the-point issues in which politicians feign interest in lieu of more pressing matters.

"They tell me that Francois has his fly open, (ooooh!!!) / That if Nicolas loses he will retire (noooo!!!)," they sing, referring to election front runner Francois Hollande and the incumbent president Nicolas Sarkozy.

Known as "La Chanson du Dimanche" or "The Sunday Song," the Paris duo are longtime friends Clement Marchand, 35, and Alexandre "Alec" Castagnetti, 36, who have collaborated for more than 15 years.

They released their first Sunday song in 2007, the year Sarkozy took office, and after taking time off for other projects, they are now back on air in parallel with the end of Sarkozy's five-year term.

"We sort of came into being along with our president, and this is a way of coming full circle," said Marchand, who plays the guitar and shares vocals with keyboardist Castagnetti.

The band debuted its fifth season in February, after Sarkozy announced his candidacy for re-election, with the song "France Forte" or "Strong France", in mocking reference to the president's campaign slogan.

Last month they performed the song as part of a gig at a Paris rally for far-left candidate Jean-Luc Melenchon, whose flag-waving supporters responded with cheers and clapping.

Standing on a truck inching its way along the street, the band exhibited its over-the-top energy, as fans sang along.

"Live they're great. They have energy," said Bastien Maubert, 25, a computer science student from Rennes in northwest France who came to Paris for the rally but was pleasantly surprised to see the band.

Over the years the duo have amassed a considerable following, with over 28 million views of the 129 videos on their "nakoneczny3" YouTube channel, an obscure reference to their cameraman's Ukrainian grandparents' last name.

With melodies ranging in genre from punk to rock to folk, they try to strike a humorous note while dissecting political statements they see as superficial and made to obfuscate.

"It's like a professor coming to class and providing just the chapter headings," said Marchand, who teaches maths to 19-year-olds as a day job, while band mate Castagnetti works as a screenwriter.

"Differential equations, you all know them ... Well, anyway, I know them," Marchand continued, impersonating a math professor who doesn't bother to explain -- a metaphor for politicians and the public.

Never intending to focus on politics, the friends quickly anchored their songs to the 2007 election campaign when they found current events to be a dependable source of inspiration.

"It was a way to find new material when every love song has already been written," said Marchand, who met Castagnetti on the first day of engineering school and now lives 200 metres (yards) from his band mate.

The pair often let chance dictate the band's course, as when they take a new look at their videos and pluck out moments of spontaneity to turn into recurrent themes.

When they realised they used "piscine" or "swimming pool" in both their first two songs -- a word not often found in song lyrics -- they decided to work it into every following song of the season.

They have since hidden a different "secret word" in the song lyrics of almost all five seasons, including the current one.

As a finale, the band will play two live shows around the time of the two-round presidential election on April 22 and May 6.